#include <stdio.h>

double factorial(unsigned int i)
{
    if (i <= 1)
    {
        return 1;
    }
    return i * factorial(i - 1);
}
int main()
{
    int i = 7;
    double result = factorial(i);
    printf("%d factorial is %.0f\n", i, result);
    return 0;
}
